Franck Azema’s men had lost top spot to Toulouse on Saturday but moved back to the top of the pile with a bonus-point win, surging clear in the second half.
Moala’s first try in the closing stages of the first half sent Clermont in with an 8-6 lead at the break, but his second – combined with the kicking of replacement scrum-half Morgan Parra – came as part of a sequence of 13 unanswered points early in the second.
Jonathan Pelissie pulled a try back shortly after the hour mark, but it was all Lyon could muster in the second 40 minutes.
Peter Betham quickly produced an answer to that Pelissie touchdown, before Alexandre Fischer secured the bonus point with Lyon down to 14 men – Hendrik Roodt sent to the sin bin.
The result sends Clermont four points clear of Toulouse, while Lyon end the weekend in sixth, with one win from their last three matches.
— ASM Rugby (@ASMOfficiel) November 25, 2018
In the day’s other match, La Rochelle leapfrogged Stade Francais to go fourth with an impressive 14-12 triumph at Stade Jean-Bouin to mark Jono Gibbes’ first game in charge.
The men from the capital led 9-5 at half-time thanks to the boot of Morne Steyn, with Jean-Charles Orioli going over for the visitors.
However, nine points off the tee from Ihaia West in the second half turned the match around for a result that puts La Rochelle firmly in the hunt at the top of the league, trailing Clermont by eight points.
Stade Francais are a point further back after a second successive defeat.
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